Lotion shampoos are widely accepted due to their ease of use, including spreading the shampoo through the hair. However, when particulate, small size active ingredients are used in lotion shampoos, suspension and deposition of those ingredients such as selenium sulfide presents a variety of problems.
The prior art discloses antidandruff shampoos containing components designed to suspend particulate matter. Japanese Application with Open for Public Inspection No. 60,810, May 19, 1977 (Lion Fat & Oil), dicloses shampoos containing 5% to 50% of an anionic surfactant, 1% to 10% of a fatty acid diethanol amide, 0.1% to 10% of an insoluble fine powder and 1% to 10% of an ethylene glycol ester. U.S. Pat. No. 4,470,982, to Winkler discloses similar compositions containing from 11% to 20% of an anionic surfactant, from 4% to 6% of a suspending agent, from 2% to 4% of an amide, a particulate antidandruff agent and water. British Patent 1,051,258, Dec. 14, 1966 to Colgate-Palmolive Company discloses selenium sulfide shampoos containing suspending agents.
While these references disclose suspending antidandruff actives, they do not provide all of the answers to the problems associated with forming such suspensions.
It has been surprisingly found by the present inventor that selenium sulfide lotion shampoo compositions utilizing xanthan gum and magnesium aluminum silicate as suspending agents are very stable and provide enhanced deposition of the selenium sulfide active.
It is an object of the present invention, therefore, to provide stable selenium sulfide lotion shampoos.
It is a further object of the present invention to provide selenium sulfide lotion shampoos utilizing a combination of xanthan gum and magnesium aluminum silicate suspending agents.
It is a still further object of the present invention to provide methods of shampooing hair with improved selenium sulfide compositions.
These and other objects will become readily apparent from the detailed description which follows.
Unless otherwise indicated, all percentages and ratios herein are by weight. Additionally, all measurements are made at 25.degree. C. in the composition or on the pure material unless otherwise specified.